1. Field of the Invention
The present invention relates to fabrics employed in web forming equipment such as papermaking and non-woven web forming equipment, and, more particularly, to forming fabrics in web forming equipment or papermaking machines.
2. Description of the Related Art
Paper is manufactured by conveying a paper furnish consisting of a slurry of cellulose fibers, water and appropriate additives onto a forming fabric or between two forming fabrics in a forming section of a paper machine. The sheet is then passed through a pressing section and ultimately through a drying section of a papermaking machine. In the case of standard tissue paper machines, the paper web is transferred from the press fabric to a Yankee dryer cylinder and then creped.
An essential part of the performance of a fabric is drainage and fiber retention. Currently, triple layer woven structures are employed for these applications due to their high dewatering capacity, fine forming surface, and high degree of width stability. New tissue making technologies associated with through air drying (TAD) place ever increasing demands on the forming fabric. Another approach to drying, offered by Voith Paper under the name ATMOS, and more completely described in International Patent Application Publication WO 2005/075736 A3 places even greater demands on the fabric. In this system, the fibrous web is carried around a partial arc of a drum and exposed to vacuum to remove water from the fibrous web.
Current triple layer woven forming fabrics are cross-machine direction bound which forms an impediment to the high drainage needed in such applications and the very fine forming surface needed for sheet formation. In other words, the sheet form needs to be well filled in, have a uniform basis weight distribution and minimal pin holes.
Thus, there exists a need in the art to provide a forming fabric that has increased width stability, drainage and fiber support means.
Furthermore, a need exists for ever increasing capacity and stability with respect to these parameters as paper forming technologies impose demands of ever increasing speed.